Study On The New Types Of Processing Of Xian-Du-Sun-Feng Tea

Xian-du-sun-feng tea belongs to flat type of green tea, mainly processed by the long-span-stir-drying machine. However, in order to increase efficiency of processing, local tea companies are accustomed to make tea with the combination of machines "platen enzyme killer+shape making machine+long-span-stir-drying machine". However, due to the irregulated and unharmonized these machines, problems such as tea shoots enzyme unevenly denatured, made tea not straight and tea quality unstable often take place. This study has developed a set of new processing techniques to make Xian-du-sun-feng tea by fresh leaves mechanical spreading, combination enzyme denaturing, multiphase shape making and drying.The mechanical spreading of fresh tea leaves could significantly increase spreading space and improve tea quality. The main parameters:quantity of fresh tea leaves1.0±0.2kg/m2, air temperature20±2℃, air humidity70-80%. indoor CO2concentration≤550mg/kg, water content of tea leaves after spreading71±1%.The machines of new processing techniques to make Xian-du-sun-feng tea included6CST50D platen enzyme killer with electricity heating, DXWS-5E microwave enzyme killer,6CLXL8/8three-phase continuously shape making machine,90model Long-span-stir-drying machine for plate shape of tea,6CHG60hexagonal drying machine and joint fittings.The key parameters of the new processing techniques to make Xian-du-sun-feng tea were the drum revolution frequency45～50HZ, setting temperature260±10℃, quantity of spreading tea leaves50kg/h, microwave input power700W×5, setting temperature140±10℃and speed at900-1000r/min in the enzyme denaturing of fresh tea leaves by the combination of platen enzyme killer and microwave enzyme killer. This could solve the problem of enzyme denaturing unevenly by using only platen enzyme killer. The three-phase continuously shape making machine was set out by the power frequency44±1HZ, first phase temperature240-290℃, second phase temperature210-260℃, third phase temperature180-230℃. The Long-span-stir-drying machine was set down with primary drying temperature180～200℃, quantity of tea leaves150±10g/pot, time3±1min; final drying temperature150±10℃, quantity of tea leaves150±10g/pot and with duration5±1min. Tea quality could be further improved by primary tea sorted out, pubescence removal and aroma increasing drying. The production capacity of the new processing techniques could be250kg/day and suitable for the medium scale Xian-du-sun-feng tea production company.